Method of and apparatus for applying ignition paste in the manufacture of photoflash lamps



Aug. 25, 1964 D. SNYDER ETAL 3,146,124

METHOD OF AND APPARATUS FOR APPLYING IGNITION PASTE IN THE MANUFACTURE OF PHOTOFLASH LAMPS '7 Sheets-Sheet 1 Filed June 29, 1961 Aug. 25, 1964 D. L. SNYDER ETAL 3,146,124

METHOD OF AND APPARATUS FOR APPLYING IGNITION PASTE IN. THE MANUFACTURE OF PHOTOFLASH LAMPS 7 Sheets-Sheet 2 Filed June 29, 1961 3,146,124 METHOD OF AND APPARATUS FOR APPLYING IGNITION PASTE D. L. SNYDER ETAL Aug. 25, 1964 IN THE MANUFACTURE OF PHOTOFLASH LAMPS '7 Sheets-Sheet 3 Filed June 29, 1961 0'. SNYDER ETAL Aug. 25, 1964 3,146,124

METHOD OF AND APPARATUS FOR APPLYING IGNITION PASTE IN THE MANUFACTURE OF PHOTOFLASH LAMPS 7 Sheets-Sheet 4 Filed June 29, 1961 TAL 3,146,124 YING IGNITION PASTE TOFLASH LA D L. SNYDER E METHOD OF AND APPARATUS FOR APPL.

IN THE MANUFACTURE OF PHO MPS Filed June 29, 1961 '7 Sheets-Sheet 5 Aug. 25, 1964 D. SNYDER ETAL 3,146,124

' METHOD OF AND APPARATUS FOR APPLYING IGNITION PASTE IN THE MANUFACTURE OF PHOTOFLASH LAMPS 7 Sheets-Sheet 6 Filed June 29. 1961 Aug. 25, 1964 D. SNYDER ETAL 3,146,124

METHOD OF AND APPARATUS FOR APPLYING IGNITION PASTE IN THE MANUFACTURE OF PHOTOFLASH LAMPS 7 Sheets-Sheet 7 Filed June 29, 1961 L 1 .1] n HR United States Patent METHOD OF AND APPARATUS FOR APPLYING IGNITIDN PASTE IN THE MANUFACTURE OF PHOTOFLASH LAMPS Donald L. Snyder, Montoursville, Donald H. Pfefferle,

William C. Fink, and Magnus Nordstrom, Williamsport, and Howard S. Painter, Linden, Pa., assignors to Sylvania Electric Products Inc, a corporation of Delaware Filed June 29, 1961, Ser. No. 120,754 8 Claims. ((11. 117-113) This invention relates to the manufacture of photoflash lamps and more particularly to the application of ignition paste or primer to the inner ends of the lead-in wires with which photoflash lamps are provided.

Over the years, most commercial photoflash lamps have been structurally similar in many respects to incandescent lamps of the type widely employed for lighting in the home, i.e., they usually comprise a lamp envelope having a re-entrant stem sealed in an end thereof and a metal base secured thereto. The re-entrant stem usually has an exhaust tube depending therefrom, a pair of lead-in wires sealed in and extending through a press with which the stem is provided, and a filament secured to the lead in wires near the inner ends thereof. The outer ends of the lead-in wires are secured to the base to define electrical contacts. In addition thereto, the photoflash lamps have a quantity of ignition paste applied to the inner ends of the lead-in wires and a quantity of shredded combustible foil distributed within the lamp envelope.

In the manufacture of photoflash lamps of this type, the primer or ignition paste is usually applied to the tips of the lead-in wires by a suitable device associated with a stem-making machine. One such device for applying primer to the tips of the lead-in wires is shown and described in U.S. Patent 2,578,627, which issued on December 11, 1951, to G. D. P. Brent. A stem machine, of the type with which a primer applicator of the type disclosed in the Brent patent may be employed, is shown and described in U.S. Patent 2,637,144, which issued on May 5, 1953, to R. M. Gardner et al. In all cases, whether these or comparable devices or machines are employed, the primer is applied to the tips of the lead-in Wires before the stem or mount is transferred to a sealing machine where the stem or mount is disposed within and sealed to a lamp envelope.

Lamp envelopes employed with the type of photoflash lamps described above have usually been blown glass bulbs. More recently, there have been made available commercially photoflash lamps employing short segments of drawn glass tubing as the lamp envelope and these lamps are substantially smaller in size than the commercial photoflash lamps which heretofore have usually employed blown glass bulbs. In the manufacture of these lamps, the lead-in wires are sealed in a press formed at one end of the tubing itself rather than in a separate stem structure which, in the case of blown bulbs, is subsequently sealed to the blown bulb lamp envelope. This structural difference presents a substantial problem insofar as when and how the primer or ignition paste is applied to the tips of the lead-in wires. The tubing-type lamp is so small that the distance between the tips of the lead-in wires to which the primer or ignition paste is applied and the press through which these wires extend and which is formed in the tubing itself is quite short, so short in fact that it precludes the application of the primer or ignition paste before the press is formed. If the primer is applied before the press is formed, the heat generated during press formation is very apt to ignite the primer.

Because of the shape and size of the article of work at 3,146,124 Patented Aug. 25, 1964 this stage of the lamp manufacturing operations, conventional primer application techniques cannot be employed. For example, one could not employ the primer applicator shown and described in the reference Brent patent (cf. FIG. 2, for example) in effecting the application of primer to the tips of the lead-in wires of the intermediate product structure with which applicants are concerned (cf. FIG. 12) because the tips of the lead-in wires are disposed quite close to the closed end of the tubing and very much removed from the open end thereof. Thus a new and different method and apparatus must be provided for effecting application of the primer go the tips of the lead-in wires of a tubing-type of flashamp.

In the development of a method of and apparatus for applying primer to photoflash lamps having tubing-type envelopes, serious consideration had to be given to the tendency of the solid components of the primer to settle out of suspension. Heretofore it has been the general practice in the art to provide some means for periodically or continuously mechanically stirring the body of primer paste in the reservoir thereof during the primer application operation because of this tendency of the solid components thereof to settle out of suspension. It was found that if this were not done, substantial variations from stem to stem occurred in the composition of the applied primer and this in turn contributed to substantial variations in the peak time of the resultant lamps. Since, as is well known to those skilled in the art, peak time variations between lamps of a given type must be maintained within very close tolerances, this factor also had to be considered.

In addition to the foregoing problem of primer composition control, there is the additional problem of quantity of primer applied since peak time is related to the quantity of primer applied as well as to the composition thereof. The quantity of the primer applied depends to a great extent on the depth of the dip, i.e., how far into the reservoir of ignition paste the tips of the lead-in wires are inserted. Thus some means must be provided for regulating this operation and insuring uniformity thereof.

In view of the foregoing, one of the principal objects of this invention is to provide flashlamps of the type described with primer, the composition and quantity of which will be such that uniform peak time within very close tolerances will be assured in the mass production of these lamps.

Another object of this invention is to provide a method of effecting the application of primer in flashlamps of the type described which readily lends itself to integration in a line of high speed lamp manufacturing equipment.

A further object of this invention is to provide an apparatus for effecting the application of primer in flashlamps of the type described which readily lends itself to integration in a line of high speed lamp manufacturing equipment.

A further object of this invention is to provide an ignition paste reservoir, the shape of which is such that mechanical stirring of the ignition paste is not necessary.

A further object of this invention is to provide an ignition paste reservoir relatively small in size and containing a relatively small quantity of ignition paste, thereby contributing substantially to the safety of its use since the ignition paste is highly flammable and has a high friction sensitivity.

A further object of this invention is the provision of automatic means for speedily and accurately adjusting the relative location of each article of work immediately before application of the primer is effected so that the depth of the dip will be uniform and the resultant mass of primer deposited on the lead-in wires will be of uniform quantity.

These and other objects, advantages and features of our invention are attained, in accordance with the principles of our invention, by providing a slender tube as the primer reservoir, the outside diameter of said tube being slightly smaller than the inside diameter of the glass tubing which comprises the lamp envelope. This slender tube reservoir is reciprocated into and out of the open end of the glass tubing which comprises the lamp envelope to effect immersion of the tips of the leadin wires in the body of ignition paste in the reservoir. Immediately before this primer application operation is effected, the relative disposition of the article of work in the machine head which carries it is adjusted to make sure that the lead-in wires of each article of work will be immersed to the same depth during each and every stroke of the slender tube reservoir. The relative location of the bottom of the reservoir is adjustable, i.e., the bottom of the reservoir is an adjustable member which may be raised within the reservoir tube to compensate for the lowering of the level of ignition paste therein during operation of the primer applicator. Means are provided for effecting this adjustment automatically, thus insuring a continuous proper ignition paste level in the reservoir without the necessity for interrupting the manufacturing operations.

In the specific embodiment of our invention, FIGURE 1 is a plan view of the apparatus for applying ignition paste and the several assemblies associated therewith, including a turret-type rotary conveyor which advances the articles of work through a plurality of work stations including the primer applicator station, a chain-type conveyor which carries the articles of work to a discharge point and a transfer mechanism which transfers the articles of work from said discharge point to a head of the rotary turret-type conveyor at its loading station.

FIGURE 2 is a side elevational view of the apparatus of FIGURE 1, with the tube positioning assembly omitted for clarity of illustration of the turrent-type rotary conveyor.

FIGURE 3 is a fragmentary detail, partly in section, of the tube transfer assembly showing the transfer of a tube from the tube feeding chain-type conveyor to the turret-type rotary conveyor.

FIGURE 4 is a plan view of the turret-type rotary conveyor with the top of the turret removed to illustrate the cam assembly associated with the heads of the turret for actuating the tube-clamping fingers of the heads.

FIGURE 5 is a fragmentary detail, partly in section, of the tube positioning assembly.

FIGURE 6 is an elevational view of the primer applicator assemblies.

FIGURE 7 is a fragmentary sectional detail of the primer tube reservoir assembly.

FIGURE 8 is a fragmentary detail of the drive assembly associated with the cam which actuates the tubeclamping fingers of FIGURE 4.

FIGURE 9 is a fragmentary detail of the drive assembly associated with a turret locking device provided for accurately positioning the turret heads during each dwell of the indexing turret-type conveyor.

FIGURE 10 is a fragmentary detail of the drive assembly associated with the tube positioning assembly of FIGURE 5.

FIGURE 11 is a fragmentary detail of the drive assembly for reciprocating the primer tube reservoir assemblies shown in FIGURES 6 and 7.

FIGURE 12 is a detail of the article of work showing the beads of ignition paste, applied by the apparatus of this invention, on the tips of the lead-in wires.

Before proceeding with the detailed description of the specific embodiment of this invention, brief reference will be made to the manufacturing operations which precede the primer application operation in the manufacture of a photofiash lamp of the type with which this invention is primarily concerned. Generally speaking, these operations involve the assemblage of several work components and the integration thereof into a unitary structure. By way of example, this may be accomplished by using a mount machine of the type shown and described in US. Patent 2,637,144, which issued on May 5, 1953, to R. M. Gardner et al., modified by a work-supporting head of the type shown and described in the co-pending application of R. S. Doron et al., Serial Number 33,293,

led June 1, 1960, and entitled Work Supporting Head for the Manufacture of Electric Lamps and the Like. As shown and described in said copending application, a substantially U-shaped segment of wire with hooks formed on the free ends thereof is fed to the work-supporting head of the machine and a glass collar is slipped over the bight of said segment of wire and fused thereto, thereby defining a button which then supports the legs of the wire in spaced relationship with respect to one another. Subsequently the bight of the U-shaped segment of wire is severed, thereby defining two separate wires which will constitute the lead-in wires of the lamp. The newly defined free ends of these wires are then flattened and a filament is attached thereto. This intermediate article of work, generally termed a mount, is then positioned inside a length of glass tubing, preferably by slipping the length of glass tubing thcreover so that the mount is disposed within the tubing and at one end thereof. This end of the tubing is then heated to a plastic state and an external press formed, thereby defining a unitary article of work comprising a lamp envelope open at one end and having a mount sealed therein at the other end thereof. The segments of the lead-in wires depending from the press are then bent back onto the press to define lamp contacts for engagement with electrical contact members in a suitable lamp receptacle such as a flashgun for example. Upon completion of these several operations, this article of work is discharged from the machine head which supported it during these operations and transferred to a conveyor, a fragmentary portion of which is shown in the accompanying drawings and described below. This is the article of work which is presented to the apparatus of this invention. It is the article of work shown in FIGURE 12 of the accompanying drawings except that in FIGURE 12 the article of work is shown with the beads of primer paste on the tips of the lead-in wires, i.e., after the operation thereon of the apparatus of this invention. As shown in FIG- URE 12, this article of work comprises a tube 1 having a press 3 formed at one end thereof. A pair of lead-in wires 5 and 7 are sealed in the press 3 and extend therethrough. The segments of these lead-in wires 5 and 7 disposed within the tube 1 are supported in spaced relationship with respect to one another by a glass button 9 and have a filament 17 attached thereto. The outer ends of these lead-in wires are bent back over the press 3 to define external lamp contacts 11 and 13 for engagement with electrical contacts in a lamp receptacle, such as in a flashgun for example. The apparatus of this invention effects the application of primer to the inner tips of the lead-in wires to thereby provide them with beads 15a of primer or ignition paste. Although the nature and composition of the primer material employed is not critical in the sense that only certain primer compositions can be used with the method and apparatus of this invention, we have found that best results are obtained when primer compositions of the types described in the co-pending application of David Y. Brouse et al., Serial Number 745,644, filed June 30, 1958, and now abandoned entitled Photofiash Lamp" or in the copending application of William C. Fink et al., Serial Number 72,963, filed December 1, 1960, now Patent No. 3,111,016, entitled Photofiash Lamp and Ignition Means Therefor, both assigned to the same assignee of this invention, are employed.

The general organization of the apparatus of this invention is illustrated in FIGURE 1. Tubes 1 are carried by a conveyor to a discharge point where a tube transfer assembly 20 removes the tubes from the conveyor. The tube transfer assembly 20 inverts the tubes 1 during transfer and deposits them in heads 30 of a turret 48 which carries the tubes through a plurality of work stations and finally releases them to a discharge chute 50.

As illustrated in FIGURES 1-3, the conveyor 16 which carries the tubes 1 to the discharge point comprises an endless chain 12 with a plurality of spaced pockets 14 mounted thereon and within which the tubes 1 are disposed. The drive of the conveyor 18 includes a sprocket 16 (FIG. 2) with which the chain 12 meshes and a sprocket shaft 18 on which the sprocket 16 is mounted. The upper reach of the conveyor chain 12 is enclosed within a frame 22.

The basic member of the tube assembly 28 is a transfer arm 24 which is fixedly attached at one end thereof to one end of a pinion shaft 26. A tube transfer finger 28 and a tube transfer finger 32 are mounted on the transfer" arm 24 near the other end thereof, the former being fixedly mounted thereon and the latter being pivotally mounted thereon. The tube transfer finger 32 is a springloaded member, normally urged to a closed position with respect to the fixed transfer finger 28 by spring 34. Opening of the finger 32 with reference to its associated finger 28 to permit a tube 1 to be received therebetween is effected as the transfer arm 24 aprroaches its normal rest position at the tube pickup station as shown in FIGS. 1-3. This finger opening means comprises a roller 36 supported on tail 38 of finger 32 and bar cam 42 attached to the conveyor chain frame 22. As may be noted particularly in FIGURE 3, the bar cam 42 lies in the path of the roller 36 as the transfer arm 24 approaches the tube pickup station. Thus the bar cam 42, through the roller 36, deflects the transfer finger 32 clockwise as viewed in FIGURE 1 sufficiently to permit partial encirclement of a tube 1 disposed in a pocket 14 on the conveyor chain 12. During the first portion of the transfer stroke of the transfer arm 24 from tube pickup to tube delivery, the loaded spring 34 will urge the finger 32 counter-clockwise as viewed in FIGURE 1 as the roller 36 rides off of bar cam 42, thus effecting a closing of the finger 32 on the tube 1 and a securing of the tube 1 between fingers 28 and 32 during the transfer stroke.

Actuation of the transfer arm 24 is effected by a rack and pinion arrangement. As noted above, one end of the transfer arm 24 is attached to one end of a pinion shaft 26. The pinion shaft 26 extends through a pinion housing 44. The pinion shaft 26 is provided, intermediate its ends and within the housing 44, with a pinion 46. The pinion 46 meshes with a rack 48 which extends downwardly and through an aperture provided therefor in the pinion housing 44. As shown in FIGURE 3, the pinion housing 44 is mounted on one end of a rod 52, the rod 52 being secured thereto by clamp 54. As shown in FIGURE 2, the rod 52 extends through and is supported by housings 56 and 58. The housing 56 is mounted on a shelf provided therefor on the top face of main support bracket 62 and the housing 58 is attached to a side face of said bracket 62. The rack 48, depending from pinion housing 44, is pinned at its lower extremity to a rack guide 64 which is slidably disposed on rod 52 between housings 56 and 58. The rod 52 is provided with a spring 53 concentric therewith and disposed thereon between rack guide 64 and a collar 55 on rod 52. The rod 52 is also provided with a stop clamp 57 attached thereto at a point below and normally spaced from housing 58.

Actuation of the tube transfer arm 24 to transfer a tube 1 from the conveyor 18 to a head 30 on the turret 40 is effected by tube transfer cam 66 on main drive shaft 68. A rocker arm 72, mounted at one end thereof on rocker arm shaft 74, is provided with a cam follower 76, intermediate its ends, which rides on tube transfer cam 66.

A connecting rod 78 connects the other end of rocker arm shaft 74 to rack guide 64. Thus the tube transfer cam 66, through the connecting rod 78 and the rack guide 64, effects reciprocation of rack 48, and rack 48, through pinion 46, efiects oscillation of tube transfer arm 24, about inion shaft 26 as a pivot, between the tube pickup and the tube delivery positions.

During the first phase of the operation of the tube transfer cam 66, the entire tube transfer assembly 20 is elevated by the rack guide 64, the pinion housing 44 and the rod 52 to which it is attached being elevated by the spring 53 abutting against collar 55. This elevation of the entire tube transfer assembly 20 continues until the stop clamp 57 on the rod 52 engages the housing 58. When this occurs, the spring-loaded tube transfer finger 32 will have closed on the tube 1 to grip it and the tube 1 will have been lifted out of the pocket 14 on the conveyor 18. With the further upward movement of the rod 52 arrested by the engagement of the stop clamp 57 thereon with the housing 58, further upward movement of rack guide 64 by cam 66 effects elevation of rack 48 only and this elevation of rack 48 effects rotation of pinion 46 and oscillation of tube transfer arm 24 to the tube delivery position.

Release of a tube 1 from the tube arm 24 to a head 30 on turret 58 is effected by a bar cam 82 attached to pinion housing 44, as shown particularly in FIGURE 3. The bar cam 82 lies in the path of roller 36 on tail 38 of finger 32 as shown particularly in FIGURE 1, and thus effects deflection of the pivotally mounted finger 32 to release the tube 1. Release of the tube 1 from the finger 32 of the tube transfer assembly 28 permits the tube 1 to drop into the sleeve 84 of head 30. A block 86 (FIGS. 2 and 3), mounted on the top face of the main support bracket 62, defines a stop for the tube 1 and arrests the free fall of the tube 1 through the sleeve 84 of the head 30. As shown in FIGURES 1-4, the turret 40 is provided with eight heads 38, each of which comprises a sleeve 84 fixedly mounted on the turret and a tube-clamping finger 88 pivotally mounted intermediate its ends on a laterally projecting ear 92 of sleeve 84. Immediately after the tube 1 bottoms on the block 86, the finger 88 is actuated, by means to be described below, to grip the tube and hold it within the sleeve 84 as the turret 48 indexes through a plurality of work stations. Indexing of the turret 40 to advance the heads 30 thereon to a plurality of work stations is effected by turret drive shaft 94 to which the turret is keyed. Since indexing of the turret 40 must be synchronized with indexing of the conveyor 10, the turret drive shaft 94 is connected to the sprocket shaft 18 of the conveyor 10 through angle gear assembly 96 as shown in FIGURE 2. The output shaft of the angle gear assembly 96 is connected to the turret drive shaft 94 and the input shaft of the angle gear assembly 96 is connected to the sprocket shaft 69.

During each complete revolution of the turret 4%), the tube-clamping finger 88 of each of the heads 38 mounted thereon must be actuated several times. The finger 88 must be opened before a head reaches the tube-receiving position where it receives a tube from the tube transfer assembly 20 and it must be closed to hold a tube at this position after the head receives it. The finger 88 must be opened at a tube-positioning station to permit an accurate positioning of the tube within the sleeve 84 of the head to insure proper primer application and closed as soon as this positioning operation has been effected. And finally, the finger 88 must be opened at the discharge station to release the tube to the discharge chute Stl. As shown in FIGURES 2 and 4, the means for actuating the fingers 88 comprises a finger actuating cam 98 supported between a cam pivot plate 182 and a cam retaining ring 104 disposed immediately beneath the turret 40. The cam pivot plate 102 is supported by the turret drive shaft 94 but it is a stationary member and does not move with it. The retaining ring 184 is attached to the cam pivot plate 102 and spaced therefrom with the cam 98 disposed therebetween.

Although the tube-clamping fingers 88 of the heads are actuated several times during each revolution of the turret 40, this is accomplished by the single cam 98. As is shown in FIGURE 4, the contour of the cam 98 is designed to perform these several operations. In FIGURE 4, the cam 98 and the heads on the turret are shown in their normal rest position immediately after an indexing stroke of the turret has been completed. When so disposed, the fingers 8$ of the heads at station H, the unloading station, and at station A, the loading station, are held open by the high segment 106 of cam 98 to permit unloading and loading of a tube 1 respectively. The fingers 38 of all the other heads are closed, each securely retaining a tube 1 therein. The turret 40 is now ready to have a tube fed to the head thereof at station A and the tube 1 in the head at station E accurately positioned. The former is accomplished by he tube transfer assembly 20 shown in FIGURES 1-3 and described above. The latter is accomplished by a tube positioning assembly illustrated in FIG- URE 10 and described below. This tube positioning assembly is disposed beneath the head at station B, the tube positioning block 1118 of which is shown in phantom in FIGURE 4. After a new tube 1 has been dropped into the sleeve 84 of the head at station A and the tube positioning finger of the tube positioning assembly has moved into the tube 1 at station B, the cam 98 is actuated to effect a clockwise movement thereof as viewed in FIGURE 4. Clockwise rotation of cam 98 is effected by counter-clockwise rotation of pivot shaft through arm 112 and link 114.

Rotation of the cam 98 in a clockwise direction displaces the high segment 106 thereof sutficiently to remove it from engagement with cam follower 116 on finger 88 of the head at station A, thus permitting spring 118 to draw the finger closed and hold tube 1 in sleeve 84.

This same clockwise rotation of cam 98 effects displacement of the lobe 120 thereon from a relative position between stations B and C to a relative position between stations A and B, i.e., from its solid position to its phantom position as shown in FIGURE 4. As the lobe 120 moves past station B it effects a momentary opening of finger 88 of the head at this station. During this brief interval when this finger 88 is open, the tube 1 therein is free to be positioned and the spring 118 associated with this finger 88 draws the finger closed on the positioned tube as the lobe 126 is further displaced past station B toward station A.

When the cam reaches the end of its clockwise rotational stroke, the turret is indexed to advance the heads thereon one station and the return or counter-clockwise rotational stroke of the cam is effected at the same time. The tube 1 in the head which was at station B has now been accurately positioned for the primer application operation which is performed at station C.

One of the features of the apparatus of this invention is the provision of two primer applicator assemblies 122 and 124 disposed adjacent to one another, somewhat tangential to the turret 4t) and located therebeneath with the primer applicator heads thereof disposed in register with the heads of the turret at stations C and D as shown in FIGURES 1, 2, 4, and 6. These primer applicator assemblies are used alternately, one being held in readiness for use when the body of primer in the reservoir of a primer head of the other drops below a predetermined level. This arrangement precludes the necessity for interruption of production during the time required to replenish the depleted reservoir.

Referring now particularly to FIGURES 2 and 6, the primer applicator assemblies 122 and 124 are supported on a support casting 126 which is in turn fixed to a main frame 128, a fragmentary portion of which is shown. The supporting casting 126 is provided with a pair of parallel upstanding rods 136 and 132 on opposite sides thereof and an elongated key 134 mounted on a central block 136 formed integral with the casting 126, the key 134 being parallel to the rods and 132. A primer applicator mounting bracket 133 of the primer applicator assembly 122 is slidably supported on the rod 130 and the key 134. A primer applicator mounting bracket 140 of the primer applicator assembly 124 is slidably supported on the rod 132 and the key 134.

Since, as noted above, the two primer applicator assemblies 122 and 124 are substantially the same, the details of only one of them will now be described. Referring now particularly to FIGURES 6 and 7, a primer tube 142 is fitted into arm 144 of mounting bracket 138, the lower end of this tube extending below arm 144 and having a nut 146 threaded thereon. The primer tube 142 defines a reservoir for a body of primer material 15. A Teflon plug 148 defines the bottom of this reservoir. This plug 148 is screwed on top of an elongated adjusting screw 150. Although the relative location of the plug 148 within the primer tube 142 may be adjusted, i.e., raised or lowered within the tube depending on the level of primer therein, its fitting therein is such that it defines a seal for the bottom of the reservoir of primer so that there will be no leakage. The elongated screw 151 is connected through a gear train 152 to a motor 154 attached to and depending from a shelf 156 of mounting bracket 138. A switch cam 153, supported on the lower end of the elongated adjusting screw 15% but not rotatable therewith, interlocks with a slide 1613 attached to and depending from shelf 156 of bracket 138. This switch cam 158 serves a dual purpose. In combination with the slide 160, the switch cam 158 serves as a guide for maintaining the elongated adjusting screw 15% in alignment. It also serves as a contact member, engageable with contact fingers 162 and 163 of indicator switches 164 and 165 respectively mounted on the central block 136 of the support casting 126. As the elongated adjusting screw is turned up by the gear train 152, the depth of the primer reservoir is decreased since the Teflon plug 143 mounted on the top of screw 150 defines the bottom of the reservoir. The relative location of the switch cam 158 with respect to the contact fingers 162 and 163 is such that the former engages and deflects the latter when the depth of the reservoir has become so shallow as to indicate substantial depletion of the primer material therein.

The switch cam 158 has an upper and a lower contact face, the former being engageable with contact finger 162 and the latter being engageable with contact finger 163. When the upper face of switch cam 15S moves into engagement with contact finger 162, it actuates the switch 164 which in turn actuates a suitable visual or audible signal, such as a lamp or buzzer, to thereby inform an operator or attendant that it is time to prepare the other primer applicator assembly for use. A time factor of about five minutes for example may be allowed for this preparation which includes the filling of the other primer tube with ignition paste and positioning it in its proper place in the other prime applicator assembly. A handle 166, fitted in a spring-loaded block 168 rotatably supported on a shaft 170, provides a ready means for releasing the primer tube 142 for refilling. Rotation of the handle 166 withdraws the block 168 from frictional engagement with the primer tube 142. In its normal rest position as shown, the block 168 is in frictional engagement with the primer tube 142.

The shaft 17% is part of the drive assembly which raises and lowers the primer applicator mounting bracket 133 and the several parts supported thereon including the primer tube 142 to move the primer tube into the tube 1 to effect application of the primer material disposed therein as shown in FIGURE 7. As shown in FIGURE 6, one end of shaft 1% terminates in bracket 138 and is secured thereto. The shaft 176 extends through the central block 136 of support casting 126 and one end of a shaft connector 1'72 is secured to the lower end thereof. As is shown in FIGURES 2 and 6, this end of the shaft connector 172 is disposed adjacent to a locking finger 174 which is movable into and out of interlocking engagement therewith. The locking finger 174 extends through and is supported by a solenoid support 176. A solenoid 178, to which the other end of locking finger 174 is connected, is mounted on a lateral extension of solenoid support 176. The solenoid support 176 is in turn mounted on solenoid support bracket 18%.

As noted immediately above, one end of shaft connector 172 is connected to the lower end of shaft 171). The shaft connector 172 extends substantially perpendicular to shaft 171 (FIG. 1) and the other end thereof is secured to a connecting rod 182 near the upper end thereof as shown in FIGURE 11.

As noted above, when the upper contact face of switch cam 153 engages contact finger 162 of switch 164, it alerts an attendant to prepare the second primer applicator assembly for operation. Operation of the second primer applicator assembly is effected automatically by the switch 165 (FIG. 6) when the contact finger 163 thereof is engaged and deflected by engagement therewith of the lower contact face of switch cam 158. When the switch 165 is actuated in this manner, it de-energizes the solenoid 178 of the first primer applicator assembly, thus permitting the finger 174 thereof to lock the shaft connector 172 and thus prevent further reciprocation of the first primer applicator assembly. It also energizes the corresponding solenoid 178 of the second primer applicator assembly, retracts the finger 174 thereof from locking engagement with its corresponding shaft connecto 172 and thus permit reciprocation of the second primer applicator assembly. It is in this manner that the second primer applicator assembly is automatically put in operation and the first primer applicator assembly is rendered inactive. Similar means are employed to render inactive the second primer applicator assembly and reactivate the first primer applicator assembly when depletion of the primer paste in the primer tube of the former occurs. In this operation, a time delay relay is employed to permit both assemblies to operate for one cycle before the second primer applicator assembly is locked out, thus making sure that no tubes are missed in this change-over.

The several drive mechanism associated with the apparatus described above are illustrated in FIGURES 811 and will now be described.

The drive for actuating the cam 98 which opens and closes the tube-clamping finger 88 of each of the heads 30 on the turret 41 is shown in FIGURE 8. As described above, the cam 98 is connected through link 114 and arm 112 to one end of pivot shaft 110. The pivot shaft 110 is rotatably supported within a shaft housing 184 fixedly attached to the main frame 128 of the machine. An arm 186, fixedly attached to the lower end of pivot shaft 1110, supports a cam follower 188 which rides on finger opening cam 1% on the main drive shaft 68. A spring 194 maintains the cam follower 188 in engagement with the cam 191}, one end of the spring being connected to a spring pin 196 depending from arm 186 and the other end thereof being connected to a spring bracket 198 mounted on a rocker shaft 2110. Thus the cam 190, through pivot shaft 110, effects clockwise and counterclockwise rotation of cam 93 as viewed in FIGURE 4 to open and close the tube clamping fingers 88 of the heads 40 at stations A and B.

The drive mechanism illustrated in FIGURE 9 provides a means for actuating a turret locking pin into interlocking relationship with respect to the turret 40 during the dwell periods of the turret. As described above, a tube positioning pin is moved up into the article of work, the tube 1, during the dwell at station B and a primer applicator tube is moved up into the tube 1 during the dwell at station C or station D. These operations make it most desirable that the heads 30 on the turret 41B dwell at stations B, C and D in exactly the same relative position every time the turret indexes. This is accomplished by a turret locking pin 292 which is reciprocated into and out of a turret locking sleeve 294 attached to and depending from the cam pivot plate 1114 at station G as shown in FIGURE 4 and into the locking hole 206 on turret 40 at this station as shown in FIGURE 1. As shown in FIGURE 9, the locking pin 2112 is attached to one end of a link 208. The other end of link 2025 is connected to one end of a rocker arm 210 pivotally mounted intermediate its ends at 212 in bracket 214 attached to main frame 123. The other end of rocker arm 210 is provided with a cam follower 216 which rides on turret locking cam 21% on main drive shaft 68. The cam follower 216 is maintained in engagement with the cam 218 by spring 220, one end of which is attached to the rocker arm 210, the other end thereof being attached to spring bracket 222 on shaft 74. Thus, immediately after each indexing stroke of the turret 40 has been completed, the turret locking pin 202 is moved up through locking sleeve 264 in cam pivot plate 1112 and into locking hole 206 at station G to lock the turret in exactly the same relative position for every dwell period, thereby insuring proper functioning of the working devices at station E and station C or D.

The tube positioning assembly and its associated drive, located at station B, is shown in FIGURE 10. The tube positioning block 1% which is a part of this assembly is shown in FIGURE 4 and was mentioned above in connection with the description thereof. The tube positioning block 103 is attached to the upper end of a shaft 224 which is reciprocative within and guided by arm 226 which is attached to main support bracket 62. A tube positioning rod 228, mounted on block 108 is reciprocative into and out of a tube 1 at station B (see also FIG. 5). The shaft 224, to one end of which the tube positioning block 1113 is fixed, is connected at its other end to one end of a link 230. The other end of link 230 is connected to one end of a rocker arm 232 which is pivotally mounted intermediate its ends on rocker arm shaft '72. A cam follower 234, supported on rocker arm 232, rides on tube positioning cam 236 mounted on the main drive shaft 68. The cam follower 234 is maintained in engagement with cam 236 by spring 238, one end of which is connected to rocker arm 232, the other end thereof being connected to a spring lever 241) on shaft 261). Thus the cam 236, through the link 230, the shaft 224 and the tube positioning block 1118 reciprocates the tube positioning rod 228 into and out of tube 1 to effect positioning thereof at station B.

The drive mechanism for reciprocating the primer tube 142 into and out of a tube 1 at station C is illustrated in FIGURE 11. As described above, particularly in connection with the description of FIGURES 6 and 7, the primer tube 142 is fitted into arm 144 of mounting bracket 138 and reciprocation of the tube 142 is effected by reciprocation of the mounting bracket 138 through shaft depending therefrom, shaft connector 172 and connecting rod 182. A rod end 242 connects the lower end of rod 182 to one end of a rocker arm 244. The rocker arm 244 is rotatably supported intermediate its ends on rocker arm shaft 200. A cam follower 246 supported on the other end of rocker arm 244 rides on primer applicator cam 248 mounted on the main drive shaft 68. A spring 250 maintains the cam follower 246 in engagement with the cam 248, one end of the spring being fixed at 252 and the other end thereof being connected to rocker arm 244. A fragmentary portion of the similar drive for the second primer applicator as sembly located at station D is also shown in this figure, this drive being shown in its rest or inactive position locked out by the mechanism described above and illustrated in FIGURE 6.

An operating cycle of the specific embodiment of the apparatus of this invention, illustrated in the drawings and described above, will now be described, reference being made initially to FIGURES 1-3. Tubes 1 are advanced, with the open ends in the up position, by the conveyor 10 to a discharge locus in register with the tube transfer fingers 28 and 32 of the tube transfer assembly 20 when said transfer assembly is disposed in its article-receiving position. With a tube 1 so disposed, the rack 48 (FIG. 3) is moved upwardly, thus rotating the pinion 45 and the pinion shaft 26. The pinion shaft 26 is rotated through about 180 degrees and thus causes the transfer arm 24 attached thereto to describe an arc of about 180 degrees. During the first few degrees of movement of the transfer arm 24, the pivotally mounted tube transfer finger 32 is permitted to close by the bar cam 42 on which roller 36 rides. Thus a tube 1 is inverted and transferred to a head 30 on turret 40 at station A of the turret. Release of the tube 1 from the transfer arm 24 of the tube transfer assembly 20 to the head 30 at station A is effected during the last few degrees of movement of the transfer arm 24 as the roller 36 rides along bar cam 82.

Each of the heads 39 of turret 40 comprises a tubereceiving sleeve 84 and a tube-clamping finger 88 as shown particularly in FIGURES 3 and 4. Thus, when a tube 1 is released from the transfer arm 24 of the tube transfer assembly 20, it drops freely within the sleeve 84 and bottoms on the stationary block 86 (FIGS. 2 and 3). As shown in FIGURE 4 and as described above in connection therewith, the spring 118 of the head 30 effects a closing of the finger 88 on the tube 1 to hold it securely within the sleeve 84 when the cam 98 is displaced sufficiently to cause the high segment 1% thereof to move out of frictional engagement with the cam follower 116 supported on the tube-clamping finger 88.

After a tube 1 has been so secured in a head 30 at station A, the turret 40 is indexed by the turret drive shaft 94 to advance this head to station E where the tube positioning assembly shown in FIGURES and is disposed. Although each and every tube 1 fed to the turret at station A bottoms on the aforementioned stationary block 86 and thus the bottom of each and every tube so fed will lie in the same horizontal plane, the relative location of the tips of the lead-in Wires is the important reference locus since it is to these tips that the primer paste is to be applied at station C or station D. Means are provided to make sure that the tips of the lead-in wires are disposed in substantially the same horizontal plane so that when primer paste is applied, the depth to which these tips are immersed in the reservoir of primer paste will be substantially uniform and uniformity of product structure in this regard in a high speed operation will be assured. Variations in the relative location of the tips of the lead-in wires occur during the preceding manufacturing operations, particularly during press formation when displacements of varying magnitudes may occur.

Adjustment of the disposition of tube 1 in the sleeve 5 is effected by tube-positioning rod 228 at station B, as shown particularly in FIGURES 5 and 10. At station B, the rod 228 and its supporting structure is elevated from the position thereof shown in solid to the position thereof shown in phantom in FIGURE 5 by the actuating assembly provided therefor shown in FIGURE 10. As described above in connection with the description of FIGURE 4, and more particularly in connection with the description of the several functions of cam 98, the finger 88 of head 30 at station B is closed on the tube 1 disposed in the sleeve 84 from the start of the dwell at this station and until the tube-positioning rod 228 has advanced to a point where it is only a fraction of an inch from the tips of the lead-in wires. The cam 98 is then actuated as described above and is shown in FIG- URE 4 to effect displacement of the lobe 120 thereof from a position between stations B and C to a position between A and B. During the travel of the lobe 120 through station B, the finger 88 is opened thereby and momentarily releases the tube 1, permitting it to drop until the tips of the lead-in wires bottom on the top of rising tube-positioning rod 228. The upward stroke of rod 228 is completed during this momentary opening of finger 88, thus positioning the tube 1 insofar as the relative location of the tips of the lead-in wires are concerned. With the tube so positioned before the lobe 129 on cam 98 has completed its travel through station B, it is ready for the finger 88 to close thereon and indexing of the turret to carry it to station C, the primer applicator station.

At station C, primer is applied to the tips of the lead-in wire by primer applicator assembly 122 shown particularly in FIGS. 2, 6 and 7, the drive means for advancing the primer reservoir into the tube 1 being shown in FIGURE 11. As described above, the primer tube 142 which comprises the reservoir for primer 15, as shown in FIGURE 7, is advanced within the tube 1 until it effects immersion of the tips of the lead-in wires therein. The primer tube 142 is then retracted leaving beads 15A of primer on the tips of the lead-in wires as shown in FIGURE 12. As was pointed out above in connection with the description of the primer applicator assembly, the bottom of the reservoir is defined by a plug 143 secured to the top of an elongated adjusting screw 150, thus providing a means for raising the plug 148 within the primer tube 142 to raise the level of the primer 15 therein and thus compensate for the drop in the primer level due to the repetitive application of primer to lead-in Wire tips. The frequency with which the primer level should be raised is largely a function of the primer composition, particularly the viscosity thereof. We have found that when primer of the type disclosed in the co-pending application of W. C. Fink et al., Serial Number 72,963, filed December 1, 1960, now Patent No. 3,111,016, entitled Photofiash Lamp and Ignition Means Therefor is used, satisfactory results are obtained when the adjusting screw 150 is turned about one-sixth of a revolution for each 6 or 7 primer applications. Revolution of the screw 150 is effected by the gear train 152 which is actuated by the motor 154. Periodic energization of the motor 154 to effect this revolution of the screw 150 is effected by a conventional switch not shown which is connected to the motor on the one hand and to a counting switch 254 (FIG. 1) disposed at station B on the other hand, the actuating arm 256 of which lies in the path of and is deflected by each tube 1 moving through station B. The said conventional switch not shown and the counting switch 254 are arranged so that the former will close to energize the motor 154 each time the latter has counted the predetermined number of work units. Although satisfactory results have been obtained with one revolution of the screw 150 for each 6 or 7 primer applications, it will be readily understood by those skilled in the art that the control arrangement may be readily adjusted to effect this elevation of the bottom of the reservoir for fewer or more primer applications if such is found to be desirable or necessary.

After primer has been applied at station C, the turret indexes and carries the tube 1 sequentially through stations D, E, F and finally to station G where it is discharged into the chute as shown in FIGURE 1 by the action of the cam 93 riding on the high segment 106 thereof as shown in FIGURE 4 and displacing the tubeclamping finger 88 from engagement with the tube 1.

What we claim is:

1. The method of applying ignition paste to the tips of the lead-in wires of a phototlash lamp mount disposed in an elongated substantially tubular lamp envelope near one end thereof, the other end of said envelope being open, said method comprising reciprocating a substantially tubular reservoir of ignition paste into and out of said envelope through said open end thereof whereby immersion of said tips of said lead-in wires in the ignition paste in said reservoir is effected.

2. In the manufacture of photoflash lamps, the method of applying ignition paste to the tips of the lead-in wires of intermediate articles of manufacture, each of which includes a photoflash lamp mount disposed at one end of an elongated substantially tubular lamp envelope, the other end of said envelope being open, said method comprising: advancing said articles sequentially to a plurality of work stations; adjusting the relative vertical disposition of each of said articles at one of said work stations whereby the tips of the lead-in wires of each of said articles are disposed in the same horizontal plane; and reciprocating, at another of said work stations, a substantially tubular reservoir of ignition paste into and out of the envelope of each of said articles of manufacture through the open end thereof whereby immersion of said tips of said lead-in wires in the ignition paste in said reservoir is effected.

3. Apparatus for applying ignition paste to the tips of the lead-in Wires of a mount assembly which includes a pair of lead-in wires supported by and located at a closed end of an elongated tube, the other end of said tube being open, said apparatus comprising: a reservoir for containing a quantity of ignition paste, said reservoir including an elongated tube and a plug defining the bottom of said reservoir, said plug being slideable within said tube; a rotatable member disposed beneath said plug and to which said plug is secured; means for reciprocating said reservoir into and out of the tube of said mount assembly to effect immersion of said leadin wire tips in the ignition paste in said reservoir; and means for rotating said rotatable member whereby the relative location of said plug within said reservoir tube is changed and the level of the ignition paste in said reservoir is thereby adjusted.

4. In apparatus for applying ignition paste to the tips of the lead-in wires of a mount assembly which includes a pair of lead-in wires supported by and located at a closed end of an elongated tube, the other end of said tube being open, the combination of: a conveyor; a plurality of work-supporting heads disposed in spaced relationship on said conveyor; means for advancing the work-supporting heads on said conveyor to a plurality of work stations; means for feeding a mount assembly to a work-supporting head on said conveyor at one of said work stations; an elongated tube defining a reservoir for a quantity of ignition paste disposed at a second of said Work stations; means for reciprocating said reservoir into and out of the tube of a mount assembly supported in a head at said second work station to effect immersion of said lead-in wire tips in the ignition paste in said reservoir; and means disposed at a third of said work stations for releasing a mount assembly supported in a head at said third work station.

5. In apparatus for applying ignition paste to the tips of the lead-in wires of a mount assembly which includes a pair of lead-in wires supported by and located at a closed end of an elongated tube, the other end of said tube being open, the combination of: a conveyor; a plurality of work-supporting heads disposed in spaced relationship on said conveyor; means for advancing the work-supporting heads on said conveyor to a plurality of work stations; means for feeding a mount assembly to a work-supporting head on said conveyor at one of said work stations; a reservoir for containing a quantity of ignition paste disposed at a second of said work stations, said reservoir including an elongated tube and a plug defining the bottom of said reservoir, said plug being slidable within said tube; means for reciprocating said reservoir into and out of the tube of a mount assembly supported in a head at said second work station to effect immersion of said lead-in wire tips in the ignition paste in said reservoir; a rotatable member disposed beneath said plug and to which said plug is secured; means for rotating said rotatable member whereby the relative location of said plug within said reservoir tube is changed and the level of the ignition paste in said reservoir is thereby adjusted; and means disposed at a third of said work stations for releasing a mount assembly supported in a head at said third work station.

6. In apparatus for applying ignition paste to the tips of the lead-in wires of a mount assembly which includes a pair of lead-in wires supported by and located at a closed end of an elongated tube, the other end of said tube being open, the combination of: a conveyor; a plurality of work-supporting heads disposed in spaced relationship on said conveyor; means for advancing the work-supporting heads on said conveyor to a plurality of work stations; means for feeding a mount assembly to a work-supporting head on said conveyor at one of said work stations; means at a second of said work stations for adjusting the relative disposition in a vertical plane of each mount assembly disposed in a head thereat to effect uniform disposition of the lead-in wire tips thereof in a common horizontal plane; an elongated tube defining a reservoir for a quantity of ignition paste disposed at a third of said work stations; means for reciprocating said reservoir into and out of the tube of a mount assembly supported in a head at said third work station to effect immersion of said lead-in wire tips in the ignition paste in said reservoir; and means disposed at a fourth of said work stations for releasing a mount assembly supported in a head at said fourth work station.

7. In apparatus for applying ignition paste to the tips of the lead-in wires of a mount assembly which includes a pair of lead-in wires supported by and located at a closed end of an elongated tube, the other end of said tube being open, the combination of: a conveyor; a plurality of work-supporting heads disposed in spaced relationship on said conveyor; means for advancing the work-supporting heads on said conveyor to a plurality of Work stations; means for feeding a mount assembly to a work-supporting head on said conveyor at one of said work stations; means at a second of said work stations for adjustnig the relative disposition in a vertical plane of each mount assembly disposed in a head thereat to effect uniform disposition of the lead-in wire tips thereof in a common horizontal plane; a reservoir for containing a quantity of ignition paste disposed at a third of said Work stations, said reservoir including an elongated tube and a plug defining the bottom of said reservoir, said plug being slideable within said tube; means for reciprocating said resevoir into and out of the tube of a mount assembly supported in a head at said third work station to effect immersion of said leadin wire tips in the ignition paste in said reservoir; a rotatable member disposed beneath said plug and to which said plug is secured; means for rotating said rotatablo member whereby the relative location of said plug within said reservoir tube is changed and the level of the ignition paste in said reservoir is thereby adjusted; and means disposed at a fourth of said work stations for releasing a mount assembly supported in a head at said fourth work station.

8. In apparatus for applying ignition paste to the tips of the lead-in of a mount assembly which includes a pair of lead-in wires supported and located at a closed end of an elongated tube, the other end of said tube being open, the combination of: a conveyor; a plurality of work-supporting heads disposed in spaced relationship on said conveyor; means for advancing the worksupporting heads on said conveyor to a plurality of work stations; means for feeding a mount assembly to a work-supporting head on said conveyor at one of said work stations; a pair of ignition paste applicator assemblies, one of which is located at a second of said work stations and the other of which is located at a third of said work stations, each of said ignition paste applicator 3,146,124 15 16 assemblies comprising an elongated tube defining a res- References Cited in the file of this patent ervoir for a quantity of ignition paste and drive means UNITED STATES PATENTS for reciprocating said reservoir into and out of the tube of a mount assembly to effect immersion of the lead-in 539,543 y y 21, 1895 Wire tips thereof in the ignition paste in said reservoir, 5 1,562,479 Whitaker 24, 1925 said drive means including a common drive shaft; and 2,449,643 Flaws P 21, 1948 means for locking out the drive means of each of said 2,692,209 Binder 19, 1954 primer applicator assemblies whereby aid assemblies 2,771,047 Zimmerman NOV. 20, 1956 may be employed alternatively to effect application of 2,832,478 Malewicz et al Apr. 29, 1958 primer paste to the tips of lead-in Wires of a mount as- 10 2,925,183 Eastus Feb. 16, 1960 sembly at said second and said third station alternatively. 2,932,412 Martin Apr. 12, 1960 

2. IN THE MANUFACTURE OF PHOTOFLASH LAMPS, THE METHOD OF APPLYING IGNITION PASTE TO THE TIPS OF THE LEAD-IN WIRES OF INTERMEDIATE ARTICLES OF MANUFACTURE, EACH OF WHICH INCLUDES A PHOTOFLASH LAMP MOUNT DISPOSED AT ONE END OF AN ELONGATED SUBSTANTIALLY TUBULAR LAMP ENVELOPE, THE OTHER END OF SAID ENVELOPE BEING OPEN, SAID METHOD COMPRISING: ADVANCING SAID ARTICLES SEQUENTIALLY TO A PLURALITY OF WORK STATIONS; ADJUSTING THE RELATIVE VERTICAL DISPOSITION OF EACH OF SAID ARTICLES AT ONE OF SAID WORK STATIONS WHEREBY THE TIPS OF THE LEAD-IN WIRES OF EACH OF SAID ARTICLES ARE DISPOSED IN THE SAME HORIZONTAL PLANE; AND RECIPROCATING, AT ANOTHER OF SAID WORK STATIONS, A SUBSTANTIALLY TUBULAR RESERVOIR OF IGNITION PASTE INTO AND OUT OF THE ENVELOPE OF EACH OF SAID ARTICLES OF MANUFAC- 